NAME

SYNOPSIS

DESCRIPTION

Test
evaluates the expression
expr.
If the value is true the exit status is null; otherwise the
exit status is non-null.
If there are no arguments the exit status is non-null.

The following primitives are used to construct
expr.

-r file

True if the file exists (is accessible) and is readable.

-w file

True if the file exists and is writable.

-x file

True if the file exists and has execute permission.

-e file

True if the file exists.

-f file

True if the file exists and is a plain file.

-d file

True if the file exists and is a directory.

-s file

True if the file exists and has a size greater than zero.

-t fildes

True if the open file whose file descriptor number is
fildes
(1 by default)
is the same file as
/dev/cons.

-A file

True if the file exists and is append-only.

-L file

True if the file exists and is exclusive-use.

-Tfile

True if the file exists and is temporary.

s1 = s2

True
if the strings
s1
and
s2
are identical.

s1 != s2

True
if the strings
s1
and
s2
are not identical.

s1

True if
s1
is not the null string.
(Deprecated.)

-n s1

True if the length of string
s1
is non-zero.

-z s1

True if the length of string
s1
is zero.

n1 -eq n2

True if the integers
n1
and
n2
are arithmetically equal.
Any of the comparisons
-ne,-gt,-ge,-lt,
or
-le
may be used in place of
-eq.
The (nonstandard) construct
-l string,
meaning the length of
string,
may be used in place of an integer.

a -nt b

True if file
a
is newer than (modified after) file
b.

a -ot b

True if file
a
is older than (modified before) file
b.

f -older t

True if file
f
is older than (modified before) time
t.
If
t
is a integer followed by the letters
y(years),M(months),d(days),h(hours),m(minutes),
or
s(seconds),
it represents current time minus the specified time.
If there is no letter, it represents seconds since
epoch.
You can also concatenate mixed units. For example,
3d12h
means three days and twelve hours ago.

These primaries may be combined with the
following operators:

!

unary negation operator

-o

binary
or
operator

-a

binary
and
operator; higher precedence than
-o

( expr )

parentheses for grouping.

The primitives
-b,-u,-g,
and
-s
return false; they are recognized for compatibility with POSIX.

Notice that all the operators and flags are separate
arguments to
test.
Notice also that parentheses and equal signs are meaningful
to
rc
and must be enclosed in quotes.

EXAMPLES

Test
is a dubious way to check for specific character strings:
it uses a process to do what an
rc(1)
match or switch statement can do.
The first example is not only inefficient but wrong, because
test
understands the purported string
-c
as an option.